Kim Jong Un goes on night stroll on Singapore's waterfront

The police said that the women were actually in a "smaller, even more restricted special zone where security is even tighter because of their proximity to where the United States of America and Democratic People's Republic of Korea leaders are staying".

The police said that the same group of South Koreans were at Sentosa in the vicinity of Capella Singapore hotel earlier on the same day where they unfurled their banners to promote their cause.

The police then found them near Shangri-La Hotel, where US President Donald Trump was staying, and in possession of protest placards.

"They were warned to leave the enhanced security special event area," said the police.

However, the group did not comply with instructions from the police to leave the area and made their way to The St Regis Singapore, which is also within the special event area.